摘要
为研究压实残积土在循环荷载作用下的变形特性,对不同含水率压实残积土进行改变围压及轴向动应力幅值条件的动三轴试验,得到了不同物理力学条件下土的动应力-应变关系滞回曲线、累积塑性应变发展规律曲线及骨干曲线,分析了动弹性模量随应变的衰变规律,探究了含水率、围压及动应力幅值等因素对试验结果的影响。结果表明:当累积塑性应变达到一定值时,压实残积土变形随动应力幅值σ_d的增大增幅明显,但最终表现为弹性安定行为,该特性随含水率的增加逐渐减弱;含水率增加不利于土样变形稳定,而提高围压可抑制该趋势。另外,增湿会加快模量的衰减,并降低残余模量,围压对衰变规律的影响随应变的增大逐渐减小。研究可为花岗岩残积土作为路基填料的施工过程及土体改良提供技术参考。
In order to study deformation characteristics of compacted residual soil under cyclic loading, dynamictri-axial tests for compacted residual soil with different moisture contents, confining pressures and amplitude conditionswere conducted. Hysteresis loops of soil dynamic stress versus strain, development law curves of cumulative plastic strainand skeleton curves of soil under different physical and mechanical conditions were obtained. The decay law of dynamicelastic modulus versus strain was analyzed. The influences of moisture content, confining pressure and dynamic stressamplitude on the test results were explored. The results showed that the deformation of compacted residual soil increasessignificantly with increase in crd when the cumulative plastic strain reaches a certain value, but the final behavior of itsdeformation is an elastic stable one, this characteristic is weakened gradually with increase in water content; increase inwater content is not conducive to the deformation stability of soil but increase in confining pressure can suppress this trend;in addition, increase in water content can speed up a delay of modulus and reduce residual modulus; the influence ofconfining pressure on the decay law of modulus decreases gradually with increase in strain. This study provided a technicalreference for the construction process of granite residual soil as roadbed filler and soil improvement
作者
尹松
孔令伟
杨爱武
穆坤
王韬
YIN Song KONG Lingwei YANG Aiwu MU Kun WANG Tao(State Key Lab of Geo-mechanics and Geotechnical Engineering, Institute of Rock and Soil Mechanics, Chinese Academy of Sciences, Wuhan 430071, China School of Civil Engineering and Architecture, Zhongyuan University of Technology, Zhengzhou 450007, China Key Laboratory of Soft Soil Characteristics and Engineering Environment of Tianjin, Tianjin 300381, China)
出处
《振动与冲击》
EI
CSCD
北大核心
2017年第11期224-231,共8页
Journal of Vibration and Shock
基金
国家自然科学基金(41372314
11672320)
中国科学院科技服务网络计划项目(KFJ-EW-STS-122)
关键词
花岗岩残积土
循环荷载
含水率
累积塑性变形
动弹性模量
granite residual soil
cyclic loading
moisture content
cumulative plastic deformation
dynamic elastic modulus
